The formulation of one-step cleaning and conditioning compositions for keratinaceous substrates, eg., human hair involves many chemical considerations. Principal among these considerations are (1) the usefulness of the composition, (2) the compatibility of the ingredients therein, and (3) the stability of the final formulation.
In formulations which employ electrolytic agents, ie., ingredients having characteristic electronic charges, it has long been problematical to find a system in which the polarity of the molecules is sufficient to leave the substrate in an improved condition but insufficient to interfere with either the function of one or more of the cleaning or surfactant ingredient(s) or the stability of the composition.
For example, stable and homogeneous compositions can usually be formulated by combining amphoteric, nonionic, and cationic surfactants with anionic detergents. Low density cationic polymers are also compatible with an excess of anionic surfactants. Such systems are, however, not very effective in conditioning hair, i.e., in improving combability. High charge density cationic polymers, which produce more pronounced conditioning effects, are incompatible with anionic detergents, and are used in combination with amphoteric or nonionic surfactants.
Compositions based on nonionic or amphoteric surfactant systems possess, however, inadequate cleansing and foaming characteristics. The compositions are also difficult to thicken.